Background:

Stanworth Crop Consultants, Inc was established as an agronomic testing facility in 1973 by Garn T. Stanworth. Les Ede, the local University of California Cooperative Extension Agent had analytical lab experience from his years at The University of California Riverside Salinity lab. He assisted Mr. Stanworth in choosing the equipment for the lab. Tom Holt was the first Chemist. Later, David Knight was contracted as an information specialist to write the software program for the computer system. Our first computers were Tandy TRS 80's utilizing a Xenix operating system. This custom program is still in use today and has been upgraded to Unix Openserver 5.0 platform.

Initially, the concept was to integrate laboratory analysis with a functioning crop consulting firm. Pest Control Advisors, Agronomists and Field Scouts would take soil and plant samples from clients fields to the new lab for nutrient analysis. Results from the samples were processed in the in-house lab and entered into a computer for reporting.

As time went on, the facility was expanded and more chemists were trained. In 1985, Bud Micalizio was employed as chemist and more tests were added to the schedule. More complimentary uses were found for the tests. Fertilizer and manure analysis wet chemistry procedures for quality and moisture content was added to the suite of services offered by the lab for fertilizer companies, feedlots, and environmental firms.

In 1992, the list of tests grew to full analysis of major and minor nutrients as an Atomic Absorption Spectrophotometer was added to the instrument list. Now, the lab consults on issues such as fertilizer micronutrient content and e. coli testing of waters, manures and soils.

Fertilizer Experience:

Stanworth Crop Consultants continues in fertilizer testing from analysis of materials such as dry commercial fertilizers to organic sources such as Mexican Guano, Feedlot Composts and Bio-solids. We also maintain contact with growers to consult on recommendations for field applications of these materials. Below are a few examples of our experience.

We assist in development of new fertilizers for suppliers of these materials. In 1988 Micro-Cal, was developed for The Pinal Company as a blend of acidified copper mine tailings with gypsum for field applications in ag and golf turf. In 1995, Ultimate Oranics LLC utilized our services in grading and formulating new liquid organic fertilizers for the organic produce industry. In 1999, RSA Microtech asked us to monitor responses on melons of new generation foliar fertilizers. In 2003, Stanworth Crop Consultants, Inc consulted with the Yakima Company on “type A” bio-solids analysis and application to agricultural fields in the Palo Verde Valley.

The primary areas we serve are: the Palo Verde Valley, Yuma Valley, Imperial Valley, Coachella Valley and the Parker Valley. We have international experience consulting on production agriculture in Mexico, China, and Saudi Arabia.

Nutrient Management:

Garn Stanworth was an early pioneer in nutrient management on crops.
He learned about nutrient needs of crops when he owned a fertilizer company in the 1950’s. He became interested in “taking the guesswork” out of nutrient applications by using laboratory analysis to guide the application timing and rates of fertilizer. Early on, he began sending soil and plant samples in the 1960’s to Ohio State University. Later on the 1970’s he built a simple lab in Blythe California to measure soil and plant Nitrogen, Phosphorus and Soil Salinity. He quickly discovered that following University guidelines of “Composite” sampling was not giving growers adequate information to manage nutrients.

Stanworth completely disagreed with the concept of composite sampling.
His direction led to a more thorough system of taking multiple samples per field on short transits (less than 300 feet) near the edge of the field. As he used to say, “It takes just as long to run 1 sample in the lab as it takes to run 4”. Wide variation was found in results in differing locations within field boundaries. These differences can be attributed to: irrigation type (border-strip, furrow), location from the head ditch (opportunity time), and differing soil types found in the field. Whatever the reason, taking multiple samples per field allowed the grower to apply different rates in different locations in the fields. Sometimes rates were modified to accommodate differing results. For example, the East ½ could have a higher rate of fertilizer compared to the, west ½ rate. Often, the field was just fertilized based upon the lowest test result found in the field. This strategy was adopted by agronomists some 20 years later in the 1990-2000’s as precision farming with GPS grid soil samples showed wide variation in nutrient levels across fields. In the early years, Garn also discovered that differing soil textures require different amounts of fertilizer. He utilized the soil “Saturation Percentage” to relate to the soil texture from the different areas of the field. He learned that sandy soils require double the amount of Phosphorus and other nutrients than the heavier texture soils. In the early 1990’s the laboratory was expanded to include secondary and micronutrient and feed testing. But the main focus of the lab was good service and turn-around time of primary nutrient needs.

Stanworth Consultant’s nutrient management strategy is service based.
Field sampling schedules are predicated by working with the grower, on the grower’s schedule. This relationship SCC has with its growers tied with a good agronomic lab means clients can have results prior to each opportunity to fertilize. Samples are regularly timed: prior to planting, at side dress, or each water run. Fields are sampled based not upon the calendar, but upon timing within the growing operation. One benefit of this paradigm is timely sampling gives crops time to respond to nutrients that have been previously applied. Conversely, sampling on a calendar basis is more arbitrary, some fields may be just coming out of a fertigation, others may be coming upon an application opportunity. Syncing sampling with irrigations gives more meaningful results and helps one understand how the crops are picking up applications and allows growers to make timely adjustments to those responses.

Season end agronomic reports are an important tool to help learn and improve management.
Stanworth’s philosophy was “if you don’t include the yields in the season end report, it doesn’t mean very much”. Stanworth’s service based consulting program includes collecting information such as planting dates, varieties to be grown, irrigation dates, fertilizer applications and even cutting dates. Pooling this information into a coherent agronomic report allows growers to understand: which varieties are producing the most yield/highest quality, which fields are responding to higher rates of fertilizer, what is the amount spent on the crop/ how to budget next year etc.